DevTools: Automatically compile snippets

BUG=none

Review-Url: https://codereview.chromium.org/2236313003
Cr-Commit-Position: refs/heads/master@{#411714}

front_end/sources/JavaScriptSourceFrame.js

@@ -68,7 +68,7 @@ WebInspector.JavaScriptSourceFrame = function(uiSourceCode)
             this._updateScriptFile(targets[i]);
     }
 
-    if (this._scriptFileForTarget.size || uiSourceCode.extension() === "js")
+    if (this._scriptFileForTarget.size || uiSourceCode.extension() === "js" || uiSourceCode.project().type() === WebInspector.projectTypes.Snippets)
         this._compiler = new WebInspector.JavaScriptCompiler(this);
 
     WebInspector.moduleSetting("skipStackFramesPattern").addChangeListener(this._showBlackboxInfobarIfNeeded, this);